improve the json handling for extra keys already there

[sperminathor]

• improve refresh_)metadata to keep extra new dict keys

python .\main_sb.py refresh_metadata https://learning.oreilly.com/library/view/learn-enough-python/9780138051143

should keep other keys already in jhson and not only the ones calculated

[obar1]

• drop at all refresh_metadata as done autmatically
• add repr